Kit sail for boats



July 3, 1962 J. H. BRODIE KIT SAIL FOR BOATS 2 Sheets-Sheet 1 Filed Aug. 1, 1960 JAMES BRODIE INVENTOR BY ROBERT M. Dunnma ATTORNEY July 3, 1 2 J. H. BRODIE 3,041,994

KIT SAIL FOR BOATS Filed Aug. 1, 1960 2 Shets-Sheet 2 25 IO j I: $.ZZT-L: [A l Fly 2 JAMES H. BkOD/E, INVENTOR BY ROBERT M. DUNNING- ATIORNEY United States Patent 3,041,994 KIT SAIL FOR BOATS James H. Brodie, 1972 Grand Ave., St. Paul 5, Minn. Filed Aug. 1, 1960, Ser. No. 46,691 8 Claims. ((11. 114-39) This invention relates to an improvement in kit sails for boats and deals particularly with a structure which may be supplied in kit form and used to convert a canoe, rowboat, or other small boat into a sail boat.

Many types of units have been produced for converting canoes, rowboats or the like into sail boats. In most instances, these units have been undesirable in that they necessitate material revision to the boat itself. For example, in most instances the sail is supported at a point substantially even with the side edges of the boat, and also at the bottom of the boat. Usually one part or the other of this support is fixed to the boat in such a way that cannot be readily removed. It is an object of the present invention to provide a sail structure which may be applied to a boat, such as a canoe, so that the boat may be driven by the wind in the manner of a sail boat. The construction is such that the unit may be added to, or removed from, a boat of the type described without modifying the boat or changing the boat in any way and that the unit is a structural entity in itself not depending on the boat hull to complete its structural pattern.

An object of the present invention resides in the provision of an attachment for canoes, rowboats and the like capable of supporting a mast in an upright position. This device includes a supporting member extending transversely across the top of the boat,and a generally V-shaped frame or bracket attached to the cross mem her and extending downwardly or upwardly therefrom. The cross member includes an aperture through which the mast may extend, and the apex of the V-shaped frame member is socketed to receive the lower end of the mast. As a result, the entire mast support is formed as a unit which may be detachably clamped to the gunwales extending along the upper edge of the boat hull.

A further feature of the present invention resides in a novel method of stopping the mast into the transverse structural assembly unit, thus eliminating the need for a mast stop secured into the bottom of the boat. By stopping the end of the mast in the bracket attached to the transverse member, the mast is supported as a cantilever entirely by the transverse member. As a result, the transverse member accommodates the fore and aft stresses of the mast in torsion, and the sideways stresses, in bending. These stresses are transmitted to the boat hull at the gunwale clamps only and hence no socket or mast stop is required in the bottom of the boat, and no rope or wire stays are required to be attached to the boat to support the mast.

A further feature of the present invention resides in the provision of a structural assembly combining the support for the mast and the attachment and support of the two leeboards which prevent sideways drifting of the boat when sailing ahead and also provide stability to the boat to resist tipping. It is usual practice to mount the leeboards by some sort of separate attachment somewhat to the rear of the mast so that the leeboards are located transversely of the center of the sail area. In the present construction, the leeboards are angled at about 45 rearwardly from the mast support so that their centroid of underwater areas are normally in the proper location relative to the center of the sail area.

A further feature of the present invention resides in the provision of a novel means of mounting the sail so that it may rotate 360 about the mast if desired. With this arrangement, the sail may be properly positioned for much simpler and easier maneuvering. For instance,

3,041,;594 Patented July 3, 1962 ice when sailing into a landing or to a dock with the wind from the stem, the boom can be allowed to swing all the way forward, spilling all the wind, and allowing the boat to drift to a gentle stop. With other types of sailing rigs, involving side stays for the mast, such stays 0bstruct full swinging of the sail and it is necessary to maneuver the boat to sail up into the wind in order to stop, a sometimes difficult sailing maneuver. Rather than to provide ropes and fillings for raising and lowering the sail, the mast extends through a hem in the vertical edge of the sail. The mast is formed of hollow tubular members. The top of the sail is supported by a pivotable member which telescopes into the top of the mast and which includes a radially extending arm designed to extend through a horizontal hem at the top of the sail.

A further feature of the present invention resides in the provision of a boat attachment of the type described in which the top swivel member not only acts to support the sail in elevated position, but also provides an increase in the area of the sail due to the fact that the sail is of trapezoidal outline, rather than triangular in outline.

A further feature of the present invention resides in the provision of a transverse mast support having leeboards on the ends thereof which extend downwardly and rearwardly at an angle of substantially 45 As a result ofthis arrangement, as the boat tends to tip to one side, the centroid of lateral resistance provided by the leeboard shifts forwardly as the leeward board is submerged deeper. This creates a force couple between the wind force on the sail and the side resistance of the leeboard against the water, which tends to turn the bow of the boat into the wind and spill the wind from the sail and thus the tendency of the boat to tip over is automatically relieved.

A further feature of the present invention resides in the provision of a transverse mast support having leeboards on the ends thereof which extend into the water and which are spaced laterally from the sides of the boat. As a result of this arrangement a stabilizing effect due to the buoyancy of the leeboards is applied t the boat. As one leeboard is submerged, when the boat tips, its additional displacement on a transverse moment arm provides a righting moment to the boat. imultaneously, as the opposite leeboard is raised clear of the water its additional deadweight on a transverse moment arm provides an equal righting moment to the boat. Thus, this feature provides for additional inherent stability to the boat.

A further feature of the present invention resides in the provision of a mast support and leeboard construction which may be clamped to, or removed from, the gunwales of the boat and to provide a rudder which may be detachably secured to the rear of the boat and by means of which the boat may be steered. With such an an rangement, it is unnecessary to bore through the boat or drive screws into the boat, thereby preventing any change in the boat structure.

These and other objects and novel features of the present invention will be more clearly and fully set forth in the following specification and claims.

FIGURE 1 is a perspective view of a boat showing the sail, leeboards, mast and mast support, as well as the rudder, attached thereto.

FIGURE 2 is a. transverse sectional view through the boat adjacent to one of the gunwales of the boat showing the manner in which the cross member may be clamped to the boat.

FIGURE 3 is a sectional view through the upper portion of the mast showing the manner in which the sail is supported.

FIGURE 4 is a side eievational view of the rudder attached to the rear of the boat.

FIGURE 5 is a top plan view of the rudder showing the manner in which the rudder is attached to the boat.

The invention comprises a kit sail designed for attachment to a boat such as the canoe A. The attachment may also be used on a row boat or similar small boat. The kit includes a mast support, a mast, a sail, leeboards, and a rudder assembly.

' The mast support is illustrated in FIGURE 1 of the drawings and includes a cross member it} designed to rest upon the gunwales of the boat to extend transversely of the boat axis. The cross member is provided with a central aperture 12 designed to accommodate the lower section 13 of the mast which is indicated in general by the numeral 14. The under surface of the cross member It} includes a pair of downwardly converging braces 15 which are connected by a center block 16. Wedge shaped blocks 17 between the braces 15 and the cross member 10 assist in thoroughly securing the wide braces to the cross member. The central member 16 is provided with a socket 19 designed to accommodate the lower end of the lower section 13 of the mast 14.

The cross member 10 extends laterally beyond the sides of the boat A and is provided with reinforcing blocks 20 at its extremities. As indicated in FIGURE 2 of the drawings, these blocks 20 are secured to the ends of the side board by any suitable means and are provided with a transverse aperture 21 extending therethrough. A bolt such as 22 extends through a leeboard 23 and through the transverse aperture 21 in the block 20. A not 24 is attached to the end of the bolt 22 to secure the leeboard 23 in place. Each of the leeboards 23 are pivotally secured to the cross member 10 in a similar manner and the angle between the leeboards and the plane of the cross member may be changed, but is usually about 45 from the horizontal.

As indicated in FIGURE 2 of the drawings, two strips of wood 25 and 26 extend transversely across the cross member 10 on opposite sides thereof. These strips 25' and 26 are somewhat longer than the width of the cross member 10 and the ends of the strips are connected by clamping bolts 27. These strips are adjustable transversely of the cross member 16 and may be clamped to hold the cross member it} against the gunwales 11 of the boat, the strip 25 extending above the cross member and the strip 26 extending beneath the gunwale as indicated in FIGURE 2. The clamping action of strips 25 and 26 transmit the torsional stresses and the shear stresses applied to the cross member 10, by the mast 14, into the hull of the boat.

The sail 29 is of generally trapezoidal shape including a hem 30 extending vertically along the forward vertical edge of the sail to accommodate the mast 14. The lower horizontal edge of the sail is provided with a hem 31 designed to accommodate an elongated boom 32 having an eye 33 at one end which is designed to encircle the lower section 13 of the mast. If desired, a cord such as 34 may be enclosed within a hem 35 in the diagonal edge of the sail, or alternatively, this diagonal edge of the sail may be merely reinforced by the hem itself.

The top portion of the sail is constructed as illustrated in FIGURE 3 of the drawings. A short rod or tube 36 is telescoped into the upper section 37 of the mast 14 and a transverse rod 39 extends through the shaft 3 6 to extend in a generally horizontal direction therefrom. The rod 39 bears upon the top of the shaft section 37 and holds the shaft 36 pivotally supported in the top of the mast. A hem 4G is provided at the upper end of the sail 29 which is designed to accommodate the rod 39. Thus the rod 39 holds the upper part of the sail in proper position. Due to the fact that the boom, the swivel formed by the shaft 36 and rod 39, and the sail itself may pivot entirely about the mast, the sail assumes 4 any desired angle relative to the boat throughout the full 360 circle.

A pair of wedge shaped blocks 41 are designed to accommodate the reinforcement 42. at the forward edge of the boat which is usually V-shaped in cross section. Arms 43 having right angmlarly turned ends 44 are supported outwardly of the blocks 41 and are designed to engage behind the edges of the reinforcement 42. A bolt 45 extends through the members 43 and through the blocks 41 to clamp these elements together. As indicated in FIGURE 4 of the drawings, the hook shaped arms 43 are longitudinally slotted so as to accommodate various widths of reinforcing members.

One of the blocks 41 is provided with a pair of vertically aligned screw eyes. A tiller board 50 is provided with a pair of similar screw eyes 49, and the rudder 47 is pivotally attached to the tiller board by a horizontal bolt so that the rudder 47 may swing upward if it strikes an underwater obstruction, or may be lifted manually. The tiller board 50 extends above the level of the rudder 47 and is pivotally connected to a tiller handle 51 by means of which the rudder may be pivoted. A pivot pin 52 extends through the screw eyes to connect the tiller board to the boat.

Because of the construction of the mast support, it may be used with virtually any type of small boat. In some instances, the cross member is connected to gunwales which extend outwardly of the boat rather than inwardly therefrom. However, the cross member 10 is of sufficient length to be useful in conjunction with virtually any boat of small size.

The assembly of the unit is extremely simple. The cross member, together with the generally V-shaped depending frame and the leeboards may be attached to the boat by merely tightening four clamping bolts. The lower section of the mast may be inserted through the cross member 10 and into the socket 19 of the suspended frame. The upper section 37 may be telescoped into the lower section. The swivel shaft 36 may be inserted into the hem 40 of the sail and the hem 30 may be threaded over the mast, the eye 33 of the boom sliding the sail downwardly. When the swivel 36 is inserted into the top of the mast section 37, the assembly of the sail itself is complete.

The rudder unit may be attached to the boat by merely tightening the clamping bolts 45 to hold the structure on the rear of the boat.

The angular leeboards are particularly advantageous in that they normally enter the water at a point generally opposite the centroid of the sail area. However, if the boat tends to tip over, the board on the leeward side of the boat becomes submerged to a greater extent, shifting the center of lateral resistance in the water forwardly toward the front of the sail. This action tends to direct the bow of the boat into the Wind, reducing the effective force of the wind upon the sail thus allowing the boat to right itself.

I claim:

1. A conversion kit for equipping a boat for sailing, said conversion kit consisting of a system of cantilevers, beams, brackets and clamps combined to function as an integral structure to transmit bending and torsional stresses applied by wind forces on a sail to a cantilever mast into the hull of a boat, said conversion kit comprising a sail, a cantilever mast supporting said sail, a transverse torsion beam to overlie and span the gunwales of a boat, a mast support bracket depending from said trans verse torsion beam, said transverse torsion beam containing at the center thereof an aperture to receive said mast, said mast support bracket being rigidly attached to said transverse torsion beam and containing thereon a socket to receive the base of said mast, said socket being spaced in a substantially vertical direction away from said aperture in said transverse torsion beam and said mast support bracket working in conjunction with said transverse torsion beam to serve as a lever arm anchoring the base of said cantilever mast to resist horizontal bending stresses in said cantilever mast and to firmly support said cantilever mast in an upright position on said transverse torsion beam, said transverse torsion beam being equipped with clamping members to grip the two opposite gunwales of a boat.

2. A conversion kit for equipping a boat for sailing, said conversion kit consisting of a system of cantilevers, beams, brackets and clamps combined as an integral structure to transmit bending and torsional stresses applied by wind forces on a sail to a cantilever mast and by hydrodynamic pressure on cantilever leeboards into the hull of a boat, said conversion kit comprising a cantilever mast supporting said sail, a transverse torsion beam to overlie and span the gunwales of a boat, a mast support bracket depending from said transverse torsion beam, said transverse torsion beam containing at the center thereof an aperture to receive said mast, said mast support bracket being rigidly attached to said transverse torsion beam and containing thereon a socket to receive the base of said mast, said socket being spaced in a substantially vertical direction away from said aperture in said transverse torsion beam and said mast support bracket working in conjunction with said transverse torsion beam to serve as a lever arm anchoring the base of said cantilever mast to resist horizontal bending stresses in said cantilever mast and to firmly support said cantilever mast in an upright position on said transverse torsion beam, said transverse torsion beam being equipped with clamping members to grip the two opposite gunwales of a boat, leeboards depending from the ends of said transverse torsion beam and adapted to extend into the water on either side of a boat.

3. The structure of claim 2, said clamping members being designed to engage and secure said transverse torsion beam and said gunwales of a boat together and said clamping members being adjustable in transverse dimension along said transverse torsion beam, said transverse adjustability serving to accommodate boats of different transverse dimension across the gunwales and said clamping means being adjustable in depth of engagement with said gunwales to accommodate boats having gunwales of difierent vertical dimension.

4. A conversion kit for equipping a boat for sailing, the conversion kit consisting of a system of cantilevers, beams, brackets and clamps combined to function as an integral structure and to transmit bending and torsional stresses applied by wind forces on a sail to a cantilever mast into said conversion kit comprising a sail, a cantilever mast supporting said sail, a transverse torsion beam to overlie and span the gunwales of a boat, a mast support bracket depending from said transverse torsion beam, said transverse torsion beam containing at the center thereof an aperture to receive said mast, said mast support bracket being rigidly attached to said transverse torsion beam and containing therein a socket to receive the base of said mast, said socket being spaced in a substantially vertical direction from said aperture in said transverse torsion beam, and said mast support bracket working in conjunction with said transverse torsion beam to serve as a lever arm anchoring the base of said cantilever mast to resist horizontal bending stresses in said cantilever mast and to firmly support said cantilever mast in an upright position on said transverse torsion beam, said transverse torsion beam being equipped with clamping members to grip the two opposite gunwales of a boat, leeboards depending from the ends of said transverse torsion beam and adapted to extend into the water on either side of a boat, said clamping members being designed to engage and secure said transverse torsion beam and said gunwales of a boat together and said clamping member being adjustable in transverse dimension along said transverse torsion beam, said adjustability serving to accommodate boats of diiferent transverse dimensions across the gunwales and said clamping means being adjustable in depth of engagement with said gunwales to accommodate boats having gunwales of difierent vertical dimension, said clamping members engaging said transverse torsion beam at a spaced interval of elongated fore and aft dimension and engaging the gunwales of a boat along an appreciable length of the fore and aft dimension, said clamping members acting as lever arms securing said transverse torsion beam to said gunwales and securing said transverse torsion beam against rotation in the fore and aft direction.

5. The structure of claim 4, said transverse torsion beam being a substantially flat member of rectangular shape in cross section and of substantially extended breadth in fore and aft dimension, designed to overlie the gunwales of a boat, said extended breadth of said transverse torsion beam spanning and engaging an appreciably extended length of said gunwales of a boat, the clamping members comprising a pair of clamping members, one on each side of said transverse torsion beam and intermediate the length between the center and the outboard ends of said transverse torsion beam, said clamping members being adjustable in transverse dimension and in depth of engagement with said gunwales of said boat, each of said pair of clamping members each consisting of two elongated bars, one of said bars above and the other of said bars below and extending substantially perpendicular to said transverse torsion beam, the said top elongated bar lying across the top of said transverse torsion beam and the said bottom elongated bar lying parallel to and underneath the flange of the gunwale of a boat, said parallel elongated bars being forcefully urged together by clamping means, securing said transverse torsion beam into pressure contact with the top edge of the gunwale of a boat, said elongated bars in gripping an appreciable length of said gunwales and engaging an appreciably elongated dimension in the fore and aft direction of said transverse torsion beam providing a lever arm to resist an overturning moment applied by said mast to said transverse torsion beam in a fore and aft plane and said lever arm transmitting said overturning moment into the gunwales of a boat, said gunwales resisting said overturning moment.

6. The structure of claim 4, said clamping members securing said transverse torsion beam downwardly to said gunwales providing an anchorage to secure said transverse torsion beam in lever fashion from uplifting from said gunwales due to side forces on said cantilever mast.

7. The structure of claim 2 and in which said leeboards are pivotally connected to the ends of said torsion beam along substantially aligned pivots.

8. The structure of claim 1 and in which said mast support bracket comprises a generally V-shaped structure with the socket adjacent to the apex of the V.

References Cited in the file of this patent UNITED STATES PATENTS 685,943 Pool Nov. 5, 1901 2,525,933 Nantz Oct. 17, 1950 2,585,599 Tchetchet Feb. 12, 1952 2,631,559 Jones Mar. 17, 1953 2,748,740 Villar June 5, 1956 

